Doorknob



FIG. 1 is a perspective view of the new design for a doorknob;

FIG. 2 is a front elevational view of the new design for a doorknob;

FIG. 3 is a top plan view of the new design for a doorknob, the bottomplan view and the left and right side elevational views being mirrorimages;

FIG. 4 is a back elevational view of the new design for a doorknob;

FIG. 5 is a perspective view of a second embodiment of the new designfor a doorknob;

FIG. 6 is a front elevational view of the second embodiment of the newdesign for a doorknob, the back view of the second embodiment beingidentical to that of the first embodiment; and,

FIG. 7 is top plan view of the new design for a doorknob, the bottomplan view and the left and right side elevational views being mirrorimages.

The broken lines in the Figures are for illustrative purposes only andform no part of the claimed design.

The ornamental design for a doorknob, as shown and described.